This invention relates to position control that permits attitude setting or positioning of one or more road-vehicle electric-powered mechanisms such as road-vehicle side windows, roof panels, seats and mirrors, and more particularly to actuation control for such electric-powered mechanisms in response to operation of switch means adapted to instruct driving of the mechanism.
In some vehicles, side windows (i.e., windows in the doors adjacent to the driver's seat and the assistant driver's seat as well as rear of the driver's seat and the assistant driver's seat), sunroofs (or roof panels), seats, mirrors outside and inside the vehicles, etc. are arranged to be driven electrically. In one example of such a vehicle, as disclosed in U.S. Pat. No. 2,848,218 of J. D. LESLIE et al, control switches are provided to selectively close an actuating circuit for forward and reverse rotation of a motor thereby to drive the motor. In another example, as disclosed in U.S. Pat. No. 4,204,255 of H. P. Cremer and UK Patent Application No. GB 2060944A of G. R. Caddick et al, an electronic control device having an advanced arithmetic function, such as a microcomputer, is used as a central control unit to monitor the current position of a movable object, so that the movable object is located at the position instructed by key switch operation.
The latter example is constructed as follows, for instance. A plurality of switches and motor drivers for electric-powered driving mechanisms are connected to the electronic control device such as a microcomputer, those among the switches adapted for designation of mechanism being operated to specify the electric-powered mechanism to be controlled and the remaining switches adapted for designation of goal position being operated to instruct the goal position in driving. Stated differently, a plurality of switches and a set of micro-computers are used to carry out both position instruction and positioning control of plural electric-powered mechanisms.
However, the prior art of this kind has encountered such problems that the number of switch means adapted to designate both electric-powered mechanism and position is increased and it is inconvenient to select the desired switch, and that the electronic control device such as a microcomputer requires many input/output ports used for reading the switches, thus resulting in the complicated structure and the higher cost of the device.